For the clouds, I had to do several tests/adjustments before it looks good enough

I used some bloom effect in this image, the problem is that this gives less contrast and in the case of a sunrise, looking at the sun, contrast is important. So I did a second render without bloom effect in higher resolution.Personally I prefer the second one, What do you think ?

What are your cloud settings? I like the sort of bumpy base of the clouds

I used clouds fractal shader V3 for better controls. then two things essentially :

1 : I lowered the coverage gamma setting at about 0.5 to get more diversity inside the clouds. 2 : In order to get some parts of the clouds base to be illuminated by the sun, I lowered the buoyancy from variation up to 0.2, this gives the base more bumpy.

Other than that there is also the softness and param C I have adjusted to get what I wanted.